On Tue, Aug 27, 2019 at 5:11 AM Alberto Bursi <alberto.bursi@xxxxxxxxxx> wrote: > If you want to fully clear cache you need to use (on an unmounted > filesystem) > > btrfs check --clear-space-cache v1 /dev/sdX > > or > > btrfs check --clear-space-cache v2 /dev/sdX I recommend a minimum version of btrfs-progs 5.1 for either of these commands. Before that version, a crash mid write of updating the extent tree can cause file system corruption. In my case, all data could be extracted merely by mounting -o ro, but I did have to recreated that file system from scratch. -- Chris Murphy
